Summary: Inspired by personal sightings near his home in Seattle, Neiwert set out to learn everything he could about orcas. The result is a thorough study of whales' behaviour and interactions with humanity from native mythology through modern-day aquarium shows. Probably more for those with specialist interest.

'Profoundly humbling experiences are good for our souls,' Neiwert asserts in the first pages of his all-encompassing book about killer whales. For him, encountering orcas, one of the world's largest mammals, has been both humbling and inspiring, reminding him that humans are just one among many wondrous species and that it is wrong for us to exploit other creatures for our own benefit. After moving to Seattle, he tried for three years to see the whales, and finally gave up; it was only when he began spending time in the places where the orcas live, simply for the pleasure of it, that he started seeing them all the time.

Whales and dolphins are extraordinary for many reasons. They are highly social beings that hunt together and communicate via echolocation. While not complex enough to be called language, their communication is still a sign of intelligence and different dialects exist in different communities. Orcas have matriarchal societies and herd herring into balls during their coordinated hunts. They have even been known to cooperate with humans in hunting other whales. Dolphins, meanwhile, help the U.S. navy locate shipwrecks. Most remarkably, cetaceans are thought to have the ability to show compassion. As Michael Parfit, a journalist who made a documentary about an orca named Luna, puts it, 'If an orca has social needs, he also has to have something that at least resembles empathy.'

Orcas are not only the ocean's top predator but also its most successful species full stop. Worldwide, however, 'apex predators' are endangered: their numbers are threatened by pollution and the decline in their food species. The dearth of Chinook salmon is a serious problem for killer whales, and they occasionally have accidents with freight ships. The year 2013 marked a record low for orca sightings in Neiwert's nearby San Juan Islands, probably due (ironically) to the disturbance caused by whale watching boats and to salmon farming.

Neiwert delves into the whales' origins – both mythological and evolutionary – and interviews experts to learn seemingly everything there is to know about them. This book was 25 years in the making, as the level of detail attests. Most enjoyable to laymen will probably be the stories of individual whales like Luna, who got separated from his pod near Vancouver Island and started seeking out human company, living there for five years until he was killed by a tugboat propeller, or the original Shamu – the name now given to all Sea World whales.

I was shocked to learn that orcas' life span is drastically reduced in captivity, with many dying in the capture attempt; and the only known cases of orcas killing humans are from places like Sea World. When one man tried to suggest whales were better off in the wild, however, he lost his aquarium job and left academia to found OrcaLab, which persuaded Greenpeace to take on whalers. This book should have the effect of convincing laymen that aquariums are not healthy places for whales and dolphins.

Some specialist interest would probably be helpful to those attempting this book, although there are plenty of black-and-white photographs to keep even casual readers interested. Neiwert's prose is somewhat undistinguished, though I did like this metaphor: 'Suspicion festered like a bad algae bloom.' Best of all are his observations on the collapsing distance between humans and animals:

experiencing that kind of deep common ground with a creature in the wild did not make them more human. It reminded me, instead, that we are all animals, and that is not always a bad thing. Love and affection, loyalty and kindness, perseverance and mercy: these are things we know in animals, too, after all.

Recovering our humanity may be the real gift of the orcas, what they can teach us. It's our choice whether to listen.